code: def node_id(self) -> Optional[str]:
      return self._dashboard_agent.get_node_id()
  
imports: import logging
  from typing import Optional, Tuple
  import concurrent.futures
  import ray.dashboard.modules.log.log_utils
  import ray.dashboard.modules.log.log_consts
  import ray.dashboard.utils
  import ray.dashboard.optional_utils
  from ray._private.ray_constants import env_integer
  import asyncio
  import grpc
  import io
  import os
  from pathlib import Path
  from ray.core.generated import reporter_pb2
  from ray.core.generated import reporter_pb2_grpc
  from ray._private.ray_constants import LOG_PREFIX_TASK_ATTEMPT_START, LOG_PREFIX_TASK_ATTEMPT_END
label_desc: Use image node_id 2 for calling the LogAgentV1Grpc obj's underlying member method code with example usage: obj.node_id() and returns: self